random allocation
(randomization, random selection*)
— The process of assigning participants in a study to treatment comparison groups using a chance process, like drawing lots, to protect against bias.; … (read more)

randomization, stratified see stratified randomization
(stratification, stratified allocation)
— The process of assigning participants in a study to treatment comparison groups based on characteristics (strata) thought to affect their prognosis; … (read more)

randomized study
(randomized control trial, RCT, randomized trial, randomized controlled trial (should not be used))
— A category of studies comparing two or more treatments in which random allocation is used to assign participants to treatment comparison groups; … (read more)

relative effect
— The ratio of outcome measures in one treatment comparison group compared to another in a study; … (read more)

reliability
— The extent to which a claim or evidence about a treatment effect is trustworthy; … (read more)

repeated measures study
— A type of non-randomized study, similar to an interrupted time series study, in which outcomes are measured in the same participants at multiple time points; … (read more)

reporting bias
(publication bias)
— Bias resulting from decisions by researchers, or others (e.g. drug companies or journal editors) not to report or publish the results of a study, or not to provide full information about a study; … (read more)

reproducibility
(repeatability, replicability)
— The extent to which the results of studies are confirmed in the results of subsequent studies; … (read more)

research
— The use of systematic and explicit methods to address questions; … (read more)